Study population
Eligible subjects were currently aged 1 to 24 years old, were post or currently receiving treatment for a malignancy, and had undergone evaluation for IO by MRI of the abdomen, heart, and/or pituitary gland. The decision to screen for IO was at the discretion of the treating oncologist and which MRI to complete was based on patient-level factors and clinical judgement. Since 2015, all patients seen in our cancer survivorship clinic are screened for IO with a serum ferritin level and referred to IO Clinic for confirmed values > 1000. To establish the cohort, all patients with a primary oncologic diagnosis that were seen at CHLA between January 1, 2007 and December 31, 2019 were identified using diagnostic and procedural billing code data from inpatient and clinic visits. Subsequently this list was cross referenced with our clinical database to identify patients with a diagnosis of cancer who had at least 1 MRI completed for IO. Patients were included regardless of disease status or treatment type.